package org.apache.lucene.index;

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.IOException;

/**
 * Expert: {@link IndexWriter} uses an instance implementing this interface to
 * execute the merges selected by a {@link MergePolicy}. The default
 * MergeScheduler is {@link ConcurrentMergeScheduler}.
 * <p>
 * <b>NOTE:</b> This API is new and still experimental (subject to change
 * suddenly in the next release)
 * </p>
 */

public abstract class MergeScheduler {

	/** Run the merges provided by {@link IndexWriter#getNextMerge()}. */
	abstract void merge(IndexWriter writer) throws CorruptIndexException,
			IOException;

	/** Close this MergeScheduler. */
	abstract void close() throws CorruptIndexException, IOException;
}
